Re: [eigen] TriangularView::coeff() fails to compile

[Martin Senst <martin.senst@xxxxxx>]

It actually works when the methods check_coordinates() and 
check_coordinates_internal() in file TriangularMatrix.h, lines 92, 104 and 109 
are declared as const.

Cheers
Martin



Am Samstag 10 Juli 2010, 21:39:29 schrieb Martin Senst:
> Hello,
> 
> the following program, with Eigen3
> 
> #include <Eigen/Eigen>
> 
> int main()
> {
>   Eigen::MatrixXd X(2, 2);
>   X.triangularView<Eigen::Upper>().coeff(0, 0);
> }
> 
> 
> results in the compiler error (sorry that it's in German)
> 
> 
> In file included from ../eigen/Eigen/Core:278:0,
>                  from ../eigen/Eigen/Dense:1,
>                  from ../eigen/Eigen/Eigen:1,
>                  from test.cpp:1:
> ../eigen/Eigen/src/Core/TriangularMatrix.h: In Elementfunktion
> »Eigen::TriangularView<MatrixType, Mode>::Scalar
> Eigen::TriangularView<MatrixType,
> Mode>::coeff(Eigen::TriangularView<MatrixType, Mode>::Index,
> Eigen::TriangularView<MatrixType, Mode>::Index) const [with _MatrixType =
> Eigen::Matrix<double, -0x00000000000000001, -0x00000000000000001>, unsigned
> int _Mode = 2u, Eigen::TriangularView<MatrixType, Mode>::Scalar = double,
> Eigen::TriangularView<MatrixType, Mode>::Index = long int]«:
> test.cpp:6:46:   instantiated from here
> ../eigen/Eigen/src/Core/TriangularMatrix.h:204:7: Fehler: Die Übergabe von
> »const Eigen::TriangularView<Eigen::Matrix<double, -0x00000000000000001,
> -0x00000000000000001>, 2u>« als »this«-Argument von »void
> Eigen::TriangularBase<Derived>::check_coordinates_internal(Eigen::Triangula
> rBase<Derived>::Index, Eigen::TriangularBase<Derived>::Index) [with Derived
> =
> Eigen::TriangularView<Eigen::Matrix<double, -0x00000000000000001,
> -0x00000000000000001>, 2u>, Eigen::TriangularBase<Derived>::Index = long
> int]« streicht Qualifizierer
> 
> 
> Is this a bug? Since coeff() only reads from the triangular view, I think
> the code above should be supported.
> 
> Cheers
> Martin